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Reverse List
kyra-ptn edited this page Aug 14, 2025
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Unit 1 Session 2 (Click for link to problem statements)
Understand what the interviewer is asking for by using test cases and questions about the problem.
Plan the solution with appropriate visualizations and pseudocode.
General Idea: Create a reversed list by looping through each element in reverse. and adding them to the beginning of another list.
1) Create a new list to hold the reversed values
2) Loop through each value in the original list, starting at the beginning index and incrementing backwards by 1
a) Add each value to the end of the new list
3) Return the new list
**Alternative Ideas:**
- Loop through each value in the original list in the forwards direction, and use the `insert()` function to add elements to the beginning of the results list.
- Use string slicing syntax.
- To visualize this strategy, it might help to try drawing out an example.
- You've most likely reversed a "list" using this strategy in real life. For example, have you ever had to reverse the order of a stack of papers? How did you do it?
def reverse_list(numbers):
reversed_list = []
for i in range(len(numbers) - 1, -1, -1):
reversed_list.append(numbers[i])
return reversed_list
Alternative Solution:
def reverse_list(numbers):
reversed_list = []
for number in numbers:
reversed_list.insert(0, number)
return reversed_list
Alternative Solution:
def reverse_list(numbers):
return numbers[::-1]